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1.
Biochim Biophys Acta Rev Cancer ; 1879(3): 189103, 2024 May.
Article in English | MEDLINE | ID: mdl-38679401

ABSTRACT

Cancer-associated cachexia (CAC) is a complex multiple organ syndrome that significantly contributes to reduced quality of life and increased mortality among many cancer patients. Its multifactorial nature makes its early diagnosis and effective therapeutic interventions challenging. Adipose tissue is particularly impacted by cachexia, typically through increased lipolysis, browning and thermogenesis, mainly at the onset of the disease. These processes lead to depletion of fat mass and contribute to the dysfunction of other organs. The ß-adrenergic signalling pathways are classical players in the regulation of adipose tissue metabolism. They are activated upon sympathetic stimulation inducing lipolysis, browning and thermogenesis, therefore contributing to energy expenditure. Despite accumulating evidence suggesting that ß3-adrenergic receptor stimulation may be crucial to the adipose tissue remodelling during cachexia, the literature remains controversial. Moreover, there is limited knowledge regarding sexual dimorphism of adipose tissue in the context of cachexia. This review paper aims to present the current knowledge regarding adipose tissue wasting during CAC, with a specific focus on the role of the ß3-adrenergic receptor, placing it as a potential therapeutic target against cachexia.


Subject(s)
Adipose Tissue , Cachexia , Lipolysis , Neoplasms , Receptors, Adrenergic, beta-3 , Signal Transduction , Cachexia/metabolism , Cachexia/pathology , Cachexia/etiology , Humans , Neoplasms/complications , Neoplasms/metabolism , Neoplasms/pathology , Receptors, Adrenergic, beta-3/metabolism , Adipose Tissue/metabolism , Adipose Tissue/pathology , Energy Metabolism , Thermogenesis , Animals
2.
Article in English | MEDLINE | ID: mdl-37966125

ABSTRACT

BACKGROUND: Aspiration pneumonia (AP) is a subset of pneumonia caused by the aspiration of food and fluids to the lungs and is highly prevalent in the older population. Oropharyngeal dysphagia (OD) is one of the risk factors for AP and it is also associated with malnutrition, dehydration and poor functional outcomes. As pneumonia is the second most common infection in nursing homes (NHs) and OD represents a major concern to NH staff, good practices for the prevention of AP in older adults at risk of OD are needed. PURPOSE: The aim of this modified e-Delphi study is to build consensus among a panel of experts regarding a set of recommendations for NH staff on good practices to prevent AP in older adults at risk of OD living in NHs. The objective of this paper is to establish the methodology inherent to the Delphi study. METHODS: An online modified Delphi study will be developed in three rounds. Criteria for the Delphi panel participants include holding a master's or doctoral degree in OD or speech and language therapy; or having 10 or more years of experience in OD; or having at least one scientific publication related to OD. A previously described modified Delphi methodology will be used to achieve consensus (75% agreement). An additional round will be performed to collect the experts' perspectives regarding the priority for application of each recommendation previously validated. DISCUSSION: This protocol aimed to describe the methodology of a future Delphi study on the prevention of AP, seeking to fulfil the gap in the literature regarding this topic. The modified Delphi technique is a widely used method for collecting experts' opinion in health sciences, but the absence of standardised guidelines allows some heterogeneity between studies with the same aim. WHAT THIS PAPER ADDS: What is already known on the subject Aspiration pneumonia (AP) is related to three main risk factors: impaired safety of swallow, impaired nutritional status and poor oral health. It is known that being dependent for feeding is one of the main risk factors for AP and around 50% of nursing home (NH) residents need feeding assistance. Thus, it is important to promote specialised intervention and care by the NH staff for preventing AP. What this paper adds to existing knowledge It is hypothesised that increasing the knowledge of NH staff regarding the best practices for preventing AP in older adults at risk of oropharyngeal dysphagia (OD) will improve outcomes such as quality of life, incidence of AP and mortality. What are the potential or actual clinical implications of this work? The recommendations resulting from this study will address a current gap in healthcare practice of NH staff regarding older adults at increased risk for OD and, consequently, for AP.

3.
Biomarkers ; 28(7): 617-627, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37942654

ABSTRACT

INTRODUCTION: High-risk human papillomavirus (HPV) is the aetiological agent of cervical cancer, which remains the fourth leading cause of cancer death in women worldwide. K14-HPV16 transgenic mice are a model for HPV-induced cancers, which undergo multistep squamous carcinogenesis at the skin, that is histologically and molecularly similar to carcinogenesis of the human cervix. Previous screens of differentially regulated microRNAs (miRs) using K14-HPV16 mice showed a role for miR-21, miR-155, miR-150, miR-146a, miR-125b and miR-223 during carcinogenesis. METHODS: We now aim to translate these observations into the clinical setting, using data provided by The Cancer Genome Atlas (TCGA) to explore whether those microRNAs can influence the survival of cervical cancer patients. RESULTS: Results showed that low miR-150, miR-155 and miR-146a expression levels in primary tumours were associated with poor overall survival. However, only miR-150 and miR-155 were found to be independent predictors, increasing the risk of death. When patients were stratified by clinical stage, low miR-150, miR-155, miR-146a and miR-125b were associated with poor survival for clinical stages I and II. Only low miR-150 expression increased the death risk. CONCLUSION: We conclude that miR-150 and miR-155 may be potentially applied as prognostic biomarkers in cervical cancer patients. However, further investigation is required to determine their applicability.


Subject(s)
MicroRNAs , Papillomavirus Infections , Uterine Cervical Neoplasms , Animals , Female , Humans , Mice , Biomarkers, Tumor/genetics , Carcinogenesis/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology , Prognosis , Uterine Cervical Neoplasms/genetics
4.
Cancers (Basel) ; 15(16)2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37627099

ABSTRACT

High-risk human papillomavirus (HPV) is etiologically related to cervical cancer, other anogenital cancers and oropharyngeal carcinomas. Low-risk HPV, especially HPV6 and HPV11, cause genital warts and laryngeal papillomas. However, the accumulating data suggests that HPV6 and HPV11 may cause malignant lesions at non-cervical anatomic sites. This review aims to estimate the proportions of single and dual HPV6/11 infections in multiple cancers reported in the last 10 years in the Cochrane, Embasa and PubMed databases. Secondly, the genomes of HPV6/11 were compared with the most common high-risk genotype, HPV16, to determine the similarities and differences. A total of 11 articles were selected, including between one and 334 HPV+ cancer patients. The frequencies of single or dual HPV6/11 infections ranged between 0-5.5% for penile and 0-87.5% for laryngeal cancers and were null for vulvar, vaginal and oral cancers. The genomic similarities between HPV6/11 and HPV16 mainly involved the E7 gene, indicating a limited ability to block cell differentiation. The presence of single or dual HPV6/11 infections in variable proportions of penile and laryngeal cancers support the vaccination strategies that cover these genotypes, not only for preventing genital warts but also for cancer prevention. Other risk factors and co-carcinogens are likely to participate in epithelial carcinogenesis associated with low-risk HPV.

5.
Crit Rev Oncol Hematol ; 186: 103989, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37061076

ABSTRACT

Among cancer patients, thrombosis and cachexia are major causes of morbidity and mortality. Although the two may occur together, little is known about their possible relationship. Thus, a literature review was conducted by screening the databases PubMed, Scopus, SciELO, Medline and Web of Science. To summarize, cancer-associated thrombosis (CAT) and cancer-associated cachexia (CAC) seem to share several patient-, tumour- and treatment-related risk factors. Inflammation alongside metabolic and endocrine derangement is the potential missing link between CAT, CAC and cancer. Many key players, including specific pro-inflammatory cytokines, immune cells and hormones, appear to be implicated in both thrombosis and cachexia, representing attractive predictive markers and potential therapeutic targets. Altogether, the current evidence suggests a link between CAT and CAC, however, epidemiological studies are required to explore this potential relationship. Given the high incidence and negative impact of both diseases, further studies are needed for the better management of cancer patients.


Subject(s)
Neoplasms , Thrombosis , Humans , Cachexia/epidemiology , Cachexia/etiology , Inflammation/complications , Neoplasms/complications , Neoplasms/epidemiology , Neoplasms/drug therapy , Thrombosis/epidemiology , Thrombosis/etiology , Crime
6.
Discov Oncol ; 14(1): 3, 2023 Jan 08.
Article in English | MEDLINE | ID: mdl-36617364

ABSTRACT

Viruses are pathogenic agents responsible for approximately 10% of all human cancers and significantly contribute to the global cancer burden. Until now, eight viruses have been associated with the development of a broad range of malignancies, including solid and haematological tumours. Besides triggering and promoting oncogenesis, viral infections often go hand-in-hand with haemostatic changes, representing a potential risk factor for venous thromboembolism (VTE). Conversely, VTE is a cardiovascular condition that is particularly common among oncological patients, with a detrimental impact on patient prognosis. Despite an association between viral infections and coagulopathies, it is unclear whether viral-driven tumours have a different incidence and prognosis pattern of thromboembolism compared to non-viral-induced tumours. Thus, this review aims to analyse the existing evidence concerning the association of viruses and viral tumours with the occurrence of VTE. Except for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infection, which are associated with a high risk of VTE, little evidence exists concerning the thrombogenic potential associated with oncoviruses. As for tumours that can be induced by oncoviruses, four levels of VTE risk are observed, with hepatocellular carcinoma (HCC) and gastric carcinoma (GC) associated with the highest risk and nasopharyngeal carcinoma (NPC) associated with the lowest risk. Unfortunately, the incidence of cancer-related VTE according to tumour aetiology is unknown. Given the negative impact of VTE in oncological patients, research is required to better understand the mechanisms underlying blood hypercoagulability in viral-driven tumours to improve VTE management and prognosis assessment in patients diagnosed with these tumours.

8.
J. physiol. biochem ; 78(2): 439-455, May. 2022.
Article in English | IBECS | ID: ibc-215971

ABSTRACT

Cachexia is associated with poor prognosis in cancer patients, and inflammation is one of its main drive factors. MicroRNAs have recently emerged as important players in cancer cachexia and are involved in reciprocal regulation networks with pro-inflammatory signaling pathways. We hypothesize that inflammation-driven cancer cachexia is regulated by specific microRNAs. The aim of this study is to explore the expression and role of inflammation-related microRNAs in muscle wasting. HPV16-transgenic mice develop systemic inflammation and muscle wasting and are a model for cancer cachexia. We employed gastrocnemius muscle samples from these mice to study the expression of microRNAs. Bioinformatic tools were then used to explore their potential role in muscle wasting. Among the microRNAs studied, miR-223-3p (p = 0.004), let-7b-5p (p = 0.034), miR-21a-5p (p = 0.034), miR-150-5p (p = 0.027), and miR-155-5p (p = 0.011) were significantly upregulated in muscles from cachectic mice. In silico analysis showed that these microRNAs participate in several processes related to muscle wasting, including muscle structure development and regulation of the MAPK pathway. When analyzing protein–protein interactions (PPI)-networks, two major clusters and the top 10 hubs were obtained. From the top 10, Kras (p = 0.050) and Ccdn1 (p = 0.009) were downregulated in cachectic muscles, as well as Map2k3 (p = 0.007). These results show that miR-223-3p, let-7b-5p, miR-21a-5p, miR-150-5p, and miR-155-5p, play a role in muscle wasting in HPV16 transgenic mice, possible through regulating the MAPK cascades. Future experimental studies are required to validate our in silico analysis, and to explore the usefulness of these microRNAs and MAPK signaling as new potential biomarkers or therapy targets for cancer cachexia. (AU)


Subject(s)
Animals , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplasms/complications , Neoplasms/genetics , Human papillomavirus 16 , Cachexia , Inflammation , Mice, Transgenic
9.
Cancers (Basel) ; 14(9)2022 Apr 28.
Article in English | MEDLINE | ID: mdl-35565345

ABSTRACT

High-risk human papillomavirus (HPV) is the etiologic agent of several types of cancer. Mast cells' role as either a driving or opposing force for cancer progression remains controversial. MicroRNAs are dysregulated in several HPV-induced cancers, and can influence mast cell biology. The aim of this study was to evaluate mast cell infiltration and to identify microRNAs potentially regulating this process. Transgenic male mice (K14-HPV16; HPV+) and matched wild-type mice (HPV−) received 7,12-Dimethylbenz[a]anthracene (DMBA) (or vehicle) over 17 weeks. Following euthanasia, chest skin and ear tissue samples were collected. Mast cell infiltration was evaluated by immunohistochemistry. MicroRNAs associated with mast cell infiltration were identified using bioinformatic tools. MicroRNA and mRNA relative expression was evaluated by RT-qPCR. Immunohistochemistry showed increased mast cell infiltration in HPV+ mice (p < 0.001). DMBA did not have any statistically significant influence on this distribution. Ear tissue of HPV+ mice showed increased mast cell infiltration (p < 0.01) when compared with chest skin samples. Additionally, reduced relative expression of miR-125b-5p (p = 0.008, 2−ΔΔCt = 2.09) and miR-223-3p (p = 0.013, 2−ΔΔCt = 4.42) seems to be associated with mast cell infiltration and increased expression of target gene Cxcl10. These results indicate that HPV16 may increase mast cell infiltration by down-regulating miR-223-3p and miR-125b-5p.

10.
Anticancer Res ; 42(5): 2443-2460, 2022 May.
Article in English | MEDLINE | ID: mdl-35489755

ABSTRACT

AIM: To evaluate the expression of lincRNA-p21, H19, EMX2OS, SNHG12 and MALAT1 in a mouse model of human papillomavirus 16 (HPV16)-induced carcinogenesis and cachexia. MATERIALS AND METHODS: Chest skin, ear, tongue, penis and gastrocnemius muscle samples from wild-type mice (HPV-) and K14-HPV16 male mice (HPV+) were collected to evaluate the expression of the selected lncRNAs using real-time PCR (qPCR). RESULTS: In chest skin and ear, H19, SNHG12, EMX2OS and lincRNA-p21 were down-regulated in HPV+ versus HPV- mice. In tongue and penile tissues, there was only down-regulation of lincRNA-p21 in HPV+ mice. Additionally, in penile tissue, lincRNA-p21 expression decreased in HPV-induced lesions comparing with normal tissues. In gastrocnemius muscle, MALAT1 was up-regulated and lincRNA-p21 was down-regulated in HPV+ versus HPV-mice. CONCLUSION: H19, SNHG12, EMX2OS and lincRNA-p21 may be involved in HPV-induced carcinogenesis. In addition, MALAT1 and lincRNA-p21 may play a role in muscle wasting and contribute to cancer cachexia.


Subject(s)
Papillomavirus Infections , RNA, Long Noncoding , Animals , Cachexia/genetics , Carcinogenesis/genetics , Female , Human papillomavirus 16/genetics , Human papillomavirus 16/metabolism , Humans , Male , Mice , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , Papillomavirus Infections/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
11.
J Physiol Biochem ; 78(2): 439-455, 2022 May.
Article in English | MEDLINE | ID: mdl-35298788

ABSTRACT

Cachexia is associated with poor prognosis in cancer patients, and inflammation is one of its main drive factors. MicroRNAs have recently emerged as important players in cancer cachexia and are involved in reciprocal regulation networks with pro-inflammatory signaling pathways. We hypothesize that inflammation-driven cancer cachexia is regulated by specific microRNAs. The aim of this study is to explore the expression and role of inflammation-related microRNAs in muscle wasting. HPV16-transgenic mice develop systemic inflammation and muscle wasting and are a model for cancer cachexia. We employed gastrocnemius muscle samples from these mice to study the expression of microRNAs. Bioinformatic tools were then used to explore their potential role in muscle wasting. Among the microRNAs studied, miR-223-3p (p = 0.004), let-7b-5p (p = 0.034), miR-21a-5p (p = 0.034), miR-150-5p (p = 0.027), and miR-155-5p (p = 0.011) were significantly upregulated in muscles from cachectic mice. In silico analysis showed that these microRNAs participate in several processes related to muscle wasting, including muscle structure development and regulation of the MAPK pathway. When analyzing protein-protein interactions (PPI)-networks, two major clusters and the top 10 hubs were obtained. From the top 10, Kras (p = 0.050) and Ccdn1 (p = 0.009) were downregulated in cachectic muscles, as well as Map2k3 (p = 0.007). These results show that miR-223-3p, let-7b-5p, miR-21a-5p, miR-150-5p, and miR-155-5p, play a role in muscle wasting in HPV16 transgenic mice, possible through regulating the MAPK cascades. Future experimental studies are required to validate our in silico analysis, and to explore the usefulness of these microRNAs and MAPK signaling as new potential biomarkers or therapy targets for cancer cachexia.


Subject(s)
MicroRNAs , Neoplasms , Animals , Cachexia/genetics , Cachexia/metabolism , Human papillomavirus 16/genetics , Human papillomavirus 16/metabolism , Inflammation , Mice , Mice, Transgenic , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplasms/complications , Neoplasms/genetics
12.
J Pediatr Endocrinol Metab ; 35(1): 73-77, 2022 Jan 27.
Article in English | MEDLINE | ID: mdl-34766743

ABSTRACT

OBJECTIVES: Since the beginning of the COVID-19 pandemic, there has been a consistent decrease in the number of admissions to the emergency department, leading to a delay in the diagnosis of several pathologies. The time from onset of symptoms to the diagnosis of Type 1 diabetes is highly variable. This treatment delay can lead to the appearance of ketoacidosis. METHODS: Retrospective study of inaugural Type 1 diabetes cases, from March 2016 to March 2021. The pandemic group was considered between March 2020 to March 2021, and the remaining period was considered as pre-pandemic. Clinical variables were analysed: duration of symptoms, weight loss and value of ketonemia and glycated haemoglobin on admission. The mean differences were considered statistically significant at p<0.05. RESULTS: 103 inaugural episodes of Type 1 diabetes were registered. The pandemic group had a lower mean age when compared to pre-pandemic group, and 51.7% of the episodes had ketoacidosis with a higher relative risk of ketoacidosis and severe ketoacidosis, when compared the pandemic with pre-pandemic group, there was a longer symptom evolution time (34 vs. 20 days), greater weight loss occurred (9.5% vs. 6.3%), the pH and HCO3 - values were lower (7.30 vs. 7.36 and 16.43 vs. 20.71 mmol/L respectively) and ketonemia was higher (5.9 vs. 2.3 mmol/L). CONCLUSIONS: The COVID-19 pandemic caused a delay in the diagnosis of Type 1 diabetes, greater length of disease, greater weight loss, higher ketonemia and lower pH and HCO3 -. There was greater ketoacidosis relative risk in pandemic group when compared to pre-pandemic group.


Subject(s)
COVID-19/epidemiology , Delayed Diagnosis/statistics & numerical data , Diabetes Mellitus, Type 1/epidemiology , Diabetic Ketoacidosis/epidemiology , SARS-CoV-2 , Severity of Illness Index , Adolescent , Child , Child, Preschool , Diabetes Mellitus, Type 1/diagnosis , Female , Humans , Infant , Infant, Newborn , Male , Odds Ratio , Portugal/epidemiology , Retrospective Studies , Risk
13.
Pharmaceuticals (Basel) ; 14(11)2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34832866

ABSTRACT

As a multifactorial and multiorgan syndrome, cancer cachexia is associated with decreased tolerance to antitumor treatments and increased morbidity and mortality rates. The current approaches for the treatment of this syndrome are not always effective and well established. Drug repurposing or repositioning consists of the investigation of pharmacological components that are already available or in clinical trials for certain diseases and explores if they can be used for new indications. Its advantages comparing to de novo drugs development are the reduced amount of time spent and costs. In this paper, we selected drugs already available or in clinical trials for non-cachexia indications and that are related to the pathways and molecular components involved in the different phenotypes of cancer cachexia syndrome. Thus, we introduce known drugs as possible candidates for drug repurposing in the treatment of cancer-induced cachexia.

14.
Crit Rev Oncol Hematol ; 168: 103541, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34801696

ABSTRACT

Tumor-infiltrating immune cells (TIICs) are critical players in the tumor microenvironment, modulating cancer cell functions. TIICs are highly heterogenic and plastic and may either suppress cancers or provide support for tumor growth. A wide range of studies have shed light on how tumor-associated macrophages, dendritic cells, neutrophils, mast cells, natural killer cells and lymphocytes contribute for the establishment of several hallmarks of cancer and became the basis for successful immunotherapies. Many of those TIICs play pivotal roles in several hallmarks of cancer. This review contributes to elucidate the multifaceted roles of immune cells in cancer development, highlighting molecular components that constitute promising therapeutic targets. Additional studies are needed to clarify the relation between TIICs and hallmarks such as enabling replicative immortality, evading growth suppressors, sustaining proliferative signaling, resisting cell death and genome instability and mutation, to further explore their therapeutic potential and improve the outcomes of cancer patients.


Subject(s)
Neoplasms , Humans , Lymphocytes, Tumor-Infiltrating , Mast Cells , Neoplasms/therapy , Signal Transduction , Tumor Microenvironment
15.
Crit Rev Oncol Hematol ; 161: 103310, 2021 May.
Article in English | MEDLINE | ID: mdl-33781867

ABSTRACT

High-risk human papillomavirus (HPV) is the most frequent sexually transmitted agent worldwide and is responsible for approximately 5% of human cancers. Identifying novel biomarkers and therapeutic targets for these malignancies requires a deeper understanding of the mechanisms involved in the progression of HPV-induced cancers. Long non-coding RNAs (lncRNAs) are crucial in the regulation of biological processes. Importantly, these molecules are key players in the progression of multiple malignancies and are able to regulate the development of the different hallmarks of cancer. This review highlights the action of lncRNAs in the regulation of cellular processes leading to the typical hallmarks of cancer. The regulation of lncRNAs by HPV oncogenes, their targets and also their mechanisms of action are also discussed, in the context of HPV-induced malignancies. Overall, accumulating data indicates that lncRNAs may have a significant potential to become useful tools for clinical practice as disease biomarkers or therapy targets.


Subject(s)
Neoplasms , Papillomavirus Infections , RNA, Long Noncoding , Gene Expression Regulation, Neoplastic , Humans , Neoplasms/genetics , Oncogenes , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , RNA, Long Noncoding/genetics
16.
J Speech Lang Hear Res ; 64(2): 464-480, 2021 02 17.
Article in English | MEDLINE | ID: mdl-33405973

ABSTRACT

Purpose The aim of the study was to provide an updated systematic review of randomized controlled trials that studied the effectiveness of pharmacological and nonpharmacological interventions to prevent aspiration pneumonia in older adults at risk for aspiration. Method The search was conducted in MEDLINE (PubMed), Scopus, and Web of Science databases and the Cochrane Central Register of Controlled Trials, using a protocol registered on PROSPERO (CRD42019139973). Randomized controlled trials of interventions to reduce the incidence of aspiration pneumonia in individuals older than 65 years at risk for aspiration, published between January 2002 and July 2019 and written in English, were included. Two reviewers independently evaluated the methodological quality of studies using the revised Cochrane risk-of-bias tool. Results Thirteen out of 703 articles identified met the eligibility criteria and were included. Six studies focused on pharmacological interventions, three studies focused on dietary interventions and compensatory strategies, one study focused on oral care, two studies focused on multidisciplinary interventions, and one study assessed a screening method. Four studies showed positive and statistically significant effect in reducing aspiration pneumonia but were considered to have unclear or high risk of bias. Three studies showed promising results on the preventive effect of pharmacological interventions. Conclusions The most recent evidence on the prevention of aspiration pneumonia in older adults revealed modest to poor methodological quality. Given the burden of aspiration pneumonia on patients and on the health care systems, the development of larger well-designed trials on this topic is of undoubted importance.


Subject(s)
Pneumonia, Aspiration , Aged , Humans , Pneumonia, Aspiration/prevention & control
17.
Mol Microbiol ; 115(5): 1005-1024, 2021 05.
Article in English | MEDLINE | ID: mdl-33368818

ABSTRACT

Differentiation from asexual blood stages to mature sexual gametocytes is required for the transmission of malaria parasites. Here, we report that the ApiAP2 transcription factor, PfAP2-G2 (PF3D7_1408200) plays a critical role in the maturation of Plasmodium falciparum gametocytes. PfAP2-G2 binds to the promoters of a wide array of genes that are expressed at many stages of the parasite life cycle. Interestingly, we also find binding of PfAP2-G2 within the gene body of almost 3,000 genes, which strongly correlates with the location of H3K36me3 and several other histone modifications as well as Heterochromatin Protein 1 (HP1), suggesting that occupancy of PfAP2-G2 in gene bodies may serve as an alternative regulatory mechanism. Disruption of pfap2-g2 does not impact asexual development, but the majority of sexual parasites are unable to mature beyond stage III gametocytes. The absence of pfap2-g2 leads to overexpression of 28% of the genes bound by PfAP2-G2 and none of the PfAP2-G2 bound genes are downregulated, suggesting that it is a repressor. We also find that PfAP2-G2 interacts with chromatin remodeling proteins, a microrchidia (MORC) protein, and another ApiAP2 protein (PF3D7_1139300). Overall our data demonstrate that PfAP2-G2 establishes an essential gametocyte maturation program in association with other chromatin-related proteins.


Subject(s)
Germ Cells/growth & development , Malaria, Falciparum/parasitology , Plasmodium falciparum/growth & development , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , Transcription Factors/metabolism , Gametogenesis , Gene Expression Regulation, Developmental , Germ Cells/metabolism , Humans , Life Cycle Stages , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Transcription Factors/genetics
18.
Int J Mol Sci ; 21(14)2020 Jul 16.
Article in English | MEDLINE | ID: mdl-32708666

ABSTRACT

Cancer cachexia is a multifactorial syndrome characterized by general inflammation, weight loss and muscle wasting, partly mediated by ubiquitin ligases such as atrogin-1, encoded by Fbxo32. Cancers induced by high-risk human papillomavirus (HPV) include anogenital cancers and some head-and-neck cancers and are often associated with cachexia. The aim of this study was to assess the presence of cancer cachexia in HPV16-transgenic mice with or without exposure to the chemical carcinogen 7,12-dimethylbenz(a)anthracene (DMBA). Male mice expressing the HPV16 early region under the control of the cytokeratin 14 gene promoter (K14-HPV16; HPV+) and matched wild-type mice (HPV-) received DMBA (or vehicle) topically over 17 weeks of the experiment. Food intake and body weight were assessed weekly. The gastrocnemius weights and Fbxo32 expression levels were quantified at sacrifice time. HPV-16-associated lesions in different anatomic regions were classified histologically. Although unexposed HPV+ mice showed higher food intake than wild-type matched group (p < 0.01), they presented lower body weights (p < 0.05). This body weight trend was more pronounced when comparing DMBA-exposed groups (p < 0.01). The same pattern was observed in the gastrocnemius weights (between the unexposed groups: p < 0.05; between the exposed groups: p < 0.001). Importantly, DMBA reduced body and gastrocnemius weights (p < 0.01) when comparing the HPV+ groups. Moreover, the Fbxo32 gene was overexpressed in DMBA-exposed HPV+ compared to control mice (p < 0.05). These results show that K14-HPV16 mice closely reproduce the anatomic and molecular changes associated with cancer cachexia and may be a good model for preclinical studies concerning the pathogenesis of this syndrome.


Subject(s)
Cachexia/etiology , Human papillomavirus 16/physiology , Neoplasms/complications , Papillomavirus Infections/complications , Animals , Body Weight , Cachexia/genetics , Cachexia/pathology , Cachexia/virology , Disease Models, Animal , Gene Expression , Human papillomavirus 16/genetics , Humans , Male , Mice, Transgenic , Muscle Proteins/genetics , Neoplasms/genetics , Neoplasms/pathology , Neoplasms/virology , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology , Papillomavirus Infections/virology , SKP Cullin F-Box Protein Ligases/genetics
19.
Cancers (Basel) ; 12(4)2020 Apr 19.
Article in English | MEDLINE | ID: mdl-32325796

ABSTRACT

Cancer cachexia or wasting is a paraneoplastic syndrome characterized by systemic inflammation and an involuntary loss of body mass that cannot be reversed by normal nutritional support. This syndrome affects 50%-80% of cancer patients, depending on the tumor type and patient characteristics, and it is responsible for up to 20% of cancer deaths. MicroRNAs are a class of non-coding RNAs (ncRNAs) with 19 to 24 nucleotides in length of which the function is to regulate gene expression. In the last years, microRNAs and other ncRNAs have been demonstrated to have a crucial role in the pathogenesis of several diseases and clinical potential. Recently, ncRNAs have begun to be associated with cancer cachexia by modulating essential functions like the turnover of skeletal muscle and adipose tissue. Additionally, circulating microRNAs have been suggested as potential biomarkers for patients at risk of developing cancer cachexia. In this review article, we present recent data concerning the role of microRNAs and other ncRNAs in cancer cachexia pathogenesis and their possible clinical relevance.

20.
J Cachexia Sarcopenia Muscle ; 11(3): 619-635, 2020 06.
Article in English | MEDLINE | ID: mdl-32142217

ABSTRACT

Cancer cachexia is a multifactorial syndrome characterized by a progressive loss of skeletal muscle mass, along with adipose tissue wasting, systemic inflammation and other metabolic abnormalities leading to functional impairment. Cancer cachexia has long been recognized as a direct cause of complications in cancer patients, reducing quality of life and worsening disease outcomes. Some related conditions, like sarcopenia (age-related muscle wasting), anorexia (appetite loss) and asthenia (reduced muscular strength and fatigue), share some key features with cancer cachexia, such as weakness and systemic inflammation. Understanding the interplay and the differences between these conditions is critical to advance basic and translational research in this field, improving the accuracy of diagnosis and contributing to finally achieve effective therapies for affected patients.


Subject(s)
Anorexia/physiopathology , Asthenia/physiopathology , Cachexia/physiopathology , Quality of Life/psychology , Sarcopenia/physiopathology , Humans
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